Tapioca flour as a thickener

Hi Y'all...
Does anyone have a recipe or suggestions of what proportions to use tapioca
flour for thickening fruit mixes when making pie, cobblers, etc. I read
about this somewhere as being infinitely better than flour, tapioca or
cornstarch because it doesn't lose its effectiveness due to the fruit
acids, but can't remember where?
Also, my boyfriend discovered that the basic recipe on file for lemon
-poppy seed scones, minus the poppy seeds and substituting vanilla yogurt
for the lemon yogurt makes a wonderful fatfree topping for a cobbler! Or
one could just use the recipe, as is, probably.
Thanks
"The body says what words cannot" Martha Graham
Anni O'Shea
Senior Research Assistant
Institute of Neuroscience
University of Oregon
Eugene, OR 97403
541-346-4596
oshea@xxxxxxxxxxxxxxxxxxx
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